The invention concerns a drive train for hoisting gears, in particular for hazardous transports, comprising a drive motor, a cable drum connected thereto, a reduction transmission arranged between the drive motor and the cable drum, a service brake provided between the drive motor and the reduction transmission and a safety brake.
If hoisting gears are provided for the transport of hazardous items, for example molten materials or also radioactive materials, a safety brake is generally also provided in the drive train, besides the service brake. The safety brake which serves for emergency stop braking is normally carried on the shaft of the cable drum.
In an emergency stop braking situation in a “lower” load situation there is a reversal in the load direction and thus a torque shock occurs in the transmission, as a consequence of different application times for the safety brake and the service brake. That torque shock leads to an overload as well as stressing in the transmission. That overload and transmission stressing which occur upon emergency stop braking result in particular from the rotating inertial masses of the motor and the transmission.